Volvo Repair: Antenna, antenna mast, volvo dealer

Question
When I turn on radio in my '96 850 the antenna goes half way and stops in the middle. It does not extend fully. The electric motor runs,   Do I need to replace only the mast?  Will I need to take the motor apart to replace the unit/mast.  Also please let em know how to replace the mast.

Answer
most the time you need hole motor it will come with antenna mast but do this order from private person i deal with  for volvo parts he has all new volvo parts  so order thru him the motor it will cost less than by volvo dealer and he will also assist you thru email how to do do it  send email to volvoparts@live.com